Potential Difference b/t 2 points

AI Thread Summary
The electric field in the problem is defined as Ex = (3.91 N/C)x, with Ey and Ez equal to zero. The potential difference VB - VA can be calculated using the formula -∫E_x dx from point A to point B. The user initially attempted to integrate E with respect to x but arrived at an incorrect result of 81.5506. Clarification was requested regarding the nature of the electric field, whether it is constant or linearly increasing. The discussion emphasizes the importance of correctly interpreting the electric field for accurate integration.
rjnara
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Ok, I've got a problem:

The electric field in a region of space has the components Ey = Ez = 0 and Ex = (3.91 N/C)x. Point A is on the y-axis at y = 2.83 m, and point B is on the x-axis at x = 3.97 m. What is the potential difference VB - VA?

I have tried integrating E (wrt x) * x from x=0..3.97 . I keep getting 81.5506, and its not the right answer. Anyhelp would be appreciated
 
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The p.d between A and B is -\int_{A}^{B}\vec{E}.d\vec{l}. In your problem this reduces to -\int_{0}^{3.97}E_xdx. Can you do it from here?
 
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rjnara said:
Ok, I've got a problem:

The electric field in a region of space has the components Ey = Ez = 0 and Ex = (3.91 N/C)x. Point A is on the y-axis at y = 2.83 m, and point B is on the x-axis at x = 3.97 m. What is the potential difference VB - VA?

I have tried integrating E (wrt x) * x from x=0..3.97 . I keep getting 81.5506, and its not the right answer. Anyhelp would be appreciated
Perhaps you could show how you are doing the integration. I am not sure about your expression for E_x. Is the field \vec{E} = 3.91\hat{x} N/C (ie. constant field of 3. 91 N/C in the x direction) or is it: \vec{E} = 3.91x\hat{x} N/C (a linearly increasing field)?

AM
 
Thanks guys :)
 
Well, tell us how you obtained your answer and answer Andrew's questions.
 
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